function Dog(name){
    this.name = name;
    this.shout=function(){
        console.log("shout from",this.name)
    }
}

var d=new Dog("adog")
d.shout()

var d2=new Dog("bdog")
d2.shout()

 var d3=new d2.constructor("cdog")
console.log(d2.constructor)
d3.shout()
